A Feedback Linearization based Generator Voltage Regulator for Power Systems

Keywords

Abstract

A new method of designing a nonlinear voltage regulator
is proposed in this paper. The regulator is based on out
put feedback linearization and can achieve both voltage
regulation and stability enhancement simultaneously. Con
ventionally output feedback linearization has been used for
voltage regulator design by taking inﬁnite bus voltage as
reference. This paper proposes to derive the control law
using the output feedback linearization approach by taking
the secondary voltage of the step-up transformer as refer
ence instead of the inﬁnite bus voltage. It has been possi
ble to considerably improve the damping performance of
the proposed regulator with this modiﬁcation. The perfor
mance of the proposed regulator is evaluated on a single
machine inﬁnite bus model of a power system at diverse
operating conditions. The simulation results show that the
performance of the proposed regulator is better or compara
ble to that of a linear static AVR equipped with a power sys
tem stabilizer and always better than that of a conventional
nonlinear voltage regulator. A linearized analysis has been
included for a better understanding of the proposed regula
tor. As the regulator design is based on local measurements
with no reference to external system parameters it could
potentially be used in a multi-machine environment.